The predecessor instrument to the present invention is manufactured by Zellweger Uster, Inc. and is known as AFIS. This instrument separated fibers and neps into one airstream and trash into another airstream using the device disclosed in U.S. Pat. No. 4,512,060. Trash is defined as foreign matter having size greater than about 50 .mu.m. Sometimes this foreign matter is called dust and trash but we shall use the designation trash here for simplicity. In this predecessor, AFIS, it was necessary to test three sets of replicate samples of textile material separately to determine information about fibers, neps and trash. One test and one separate sample of textile material was necessary for each type of entity for each replicate. Although this AFIS provided the best data available at the time for automated and fast textile testing instruments, there was a need for better data and increased speed. An improved sensor was discovered and is disclosed in the copending application Ser. No. 07/493,961, and the instrument incorporating the improved sensor, also known as AFIS, is manufactured by Zellweger Uster, Inc. For clarity and consistency with the references, the first instrument is called AFIS 0 and the instrument with the improved sensor is called AFIS 1.
The present invention is a further improvement in AFIS 1 and is directed primarily to testing rate considerations. It was first discovered that the improved sensor of AFIS-1 produced data that would enable substantially simultaneous measurement of multiple data from the same sample of textile material. By substantially simultaneous it is meant that nep data, fiber data and trash data are obtained by testing a single sample of textile material and detecting and measuring substantially all of the neps and trash and detecting and measuring a representative sample of the fibers. Thus, this improvement eliminates the need to run three separate tests on typically 3-5 replicates of three separate samples to obtain data for neps, trash and fiber. Also, it was discovered that such data could be obtained using only one sensor, if desired. The testing speed improvements discussed above are made possible by a new analyzer circuit, which is a hybrid analog and digital circuit in the preferred embodiment. Speed of operation is increased by a factor of three in the present invention as compared to AFIS 1 or AFIS 0.
With the increased speed or rate of testing achieved by the above described improvement, there arose a need for automation to insure timely supply of sample to the testing instrument. Specifically, there arose a need for an automatic feed mechanism that handles delicate samples, rapidly supplies them to the testing instrument and frees the operator for substantial periods of time. Such automation has not been successfully attempted previously because of the need for a long, slender, elongate sample of textile material and the perceived need to hand form the sample and gently hand feed the fragile sample into the testing instrument. The present instrument provides a new automatic feed mechanism that can handle the delicate elongate slender samples that are needed by an instrument testing textile samples.